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1000w smps based on LUDO3232

Hi fellas, I am building a smps based on Ludo 3232 but with a different arrangement. I would like to take some comments about the arrangement of the pcb layout and if the spacing is adequate. The pdf is attached please take a look.IMG_0302.JPGIMG_0303.JPGIMG_0304.JPGIMG_0306.jpg

Finally I designed and etched the PCB after a lot of hard work, Here are a few pics of my progress on this 1000w smps based on Ludo schematic with some alterations and design. I will test it as soon I receive the output caps from aliexpress.

Very nice work Silvio, it's looking good, and the black silk screen printed on the other side of your PCB where are the parts should go is also a very nice touch! It does look like quite a waste of the transformer though, looking at how little windings there are on the transformer. That's an ETD49, correct? I'm also busy with designing a 1KW SMPS, though I'm still deciding whether it will be a half or a full bridge. However, I'll be using either an E42/50 with Ferroxcube 3C90 ferrite, or more likely even an ETD39 with 3C95. I'll be using copper tape, to maximise the transformer efficiency.

Hi Lucas I used litz wire to wind my transformer with 70 strands of 0.16mm for primary and 60 strands of 0.16mm for secondary. The winding fill was around 7/8 and not much space was left though. I also included a Faraday screen in it to suppress interference as much as possible. I began my initial tests and its working quite well. I am finishing my Mains isolator power source so that I can give it a good load and establish the snubber network, check and set the short circuit protection. BTW my smps is for 80-0-80 volts out at 235vac input.
Copper tape seems better though giving maximum coupling between windings. Be careful with insulation though not too much and not too little. It is good practice that the copper foil will be a little less than the bobbin width say 2 or 3mm, but the insulation tape will be the full width of the bobbin. This will help with better insulation and less creapage voltages along the edges of the winding foil.
I will be glad to see your progress with some pics when you start your project.

Here are a few pics of my progress on the isolating transformer for SMPS testing. This is capable of around a KW or more at 220volts out. This was taken out of an old amplifier capable of 3kw output. I am fitting it in an old UPS box. Probbably this will power my whole workbench in the future.
My progress so far I have to continue today and try to finish it

Ah, okey, I can see in the later pictures that you did indeed fill up almost all the winding space. I thought that the pictures in your first post in this thread was showing all the windings you put on it, so that was my mistake! An isolating transformer is definitely a very useful bit of kit when building any offline SMPS. I'll be using an USB oscilloscope connected to a laptop which doesn't have a grounded plug, so that should take care of the problem for me, as an oscilloscope is pretty much essential, especially when you're making a high powered SMPS off of your own design instead of someone else's. I'll post any pictures as soon as I start with my 1KW project.

Hi Lucas, I made my first test today though I did not receive the output caps and had only a couple of 470uf at 200v that I put on temporarily. I adjusted the ringing and fitted the snubbers on the drain source of the switching fets. I did some experimentation with different values and found the best combination with the smps loaded at around 400 watts. I managed to get around 1100watts out of it with resistive loads attached to the output. Load was 9 amp at 122 volts. However the output of the isolation trafo is rated at 200 volts and and not 220 as I first taught it is. I guess I have to add a few turns to it to get 220 at least. My set up was with and isolated oscilloscope and with the isolation power transformer. I still have to try it on mains. My output voltage is calculated at 78-0-78 with 230 volts input. getting within the ripple at load I guess it will sag to about 130-140 volts on full load. I also adjusted the over current protection and I set it to cut at 10amp load. This works very good and Ludo made a good job here in design. I am posting my schematic so that you can take a look on what I have worked on.